Heretofore, a litter box for animals such as cats and dogs kept as pets is provided with a box-like litter container with an open upper part and granular animal litter contained in the litter container. As a type of a litter box for animals, a unit animal litter box provided with: an upper container the bottom of which is configured to be liquid permeable; and a lower container arranged below the upper container and in which a liquid absorbent member is placed has been known. In such a unit animal litter box, animal litter is placed in the upper container, and animal urine passes through the animal litter placed in the upper container and is absorbed by the liquid absorbent member in the lower container.
The animal litter for the unit animal litter box preferably has superior liquid permeability in order to quickly transfer a large quantity of liquid excreted during urination by an animal etc. to the lower container. In addition, a small amount of liquid remaining on a surface of the litter needs to be absorbed by the litter with the lapse of time, in order to prevent an odor. As discussed above, the litter for the unit animal litter box is required to have, simultaneously, liquid permeability and property of absorbing the liquid remaining on the surface thereof.
As such animal litter used for the unit animal litter box, animal litter configured of a plurality of granules, the granule including a group of particles configured of an inorganic porous material and a binder which binds the group of particles together has been proposed (refer to Patent Document 1).
The animal litter according to the abovementioned art can absorb the liquid remaining on the surface thereof with the lapse of time.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2008-193938